The OH X-2 Pi product state distribution arising from quenching of electronically excited OH A(2)Sigma(+) by O-2 and CO2 under single collision conditions has been determined using a pump-probe technique. For both collision partners, the majority of OH X-2 Pi products are observed in their lowest vibrational level, upsilon '' = 0, with significantly less population in upsilon '' = 1. The OH products from quenching by O-2 are generated with a substantial degree of rotational excitation, peaking around N '' approximate to 17, with an average rotational energy of similar to 4800 cm(-1), whereas OH products from quenching by CO2 exhibit a moderate degree of rotational excitation, peaking around N '' approximate to 5, with an average rotational energy of similar to 1800 cm(-1). The branching fraction into OH X-2 Pi products states reveals that nonreactive quenching is a significant decay pathway for both systems, accounting for at least 40(1)% of the quenched products with O2 and 64(5)% with CO2.